1. Field of the Invention
The invention relates to an electric plug and socket connector provided with resilient end-pressure contacts.
When it is a matter of interrupting the passage of a current in a circuit under voltage, the only known manner is to separate and to space apart two elements of said circuit. However, after the separation, the current continues to pass through an arc which sparks between the points of separation. This electric arc is constituted by a flow of electrons and by a flow of ions in reverse directions, created by the electric field which exists between the two separated parts of the circuit. This arc is all the greater as the electric field is more intense and results in numerous drawbacks of which one notably is rapid deterioration of the contact elements.
2. Description of the Prior Art
Numerous cutoff devices have been devised to render this arc unstable as rapidly as possible. Such switches or circuit-breakers call upon various techniques: switches with insulating plates, circuit-breakers with magnetic blow-out, with air sweep to remove the ionized particles and to cool the plasma, oil cut-off, vacuum cut-off, etc. In addition, it is clear that one parameter of attenuation is the speed of cut-off which enables the electric arc to be drawn out rapidly.
All these switches are intended to equip heavy current circuits, and in addition can be arranged upstream of a contacter which controls said switch by means, for example, of pilot wires so that the level of said contacter, the closing and opening, is carried out without voltage.
It is evident that such means can not be contemplated to cooperate with or equip electrical connectors of average or low current, for industrial or domestic use. The latter are, however, also subject to the disturbing influences of electric arcs, and up to the present no means of weakening electric arcs has been produced, which considerably limits the life span of conventional power sockets through the inevitable wear of the contacts and of the insulating elements which results from such arcing.
Accordingly, it is a particular object of the invention to provide an electrical plug and socket connector capable of reducing the effects of the cut-off arc.
Such connectors or power sockets comprise a fixed socket, base or housing, connected to the installation and a movable plug connected to the supply cable. For obvious safety reasons, certain bases are provided with a protective disc, also called safety disc, which is mounted on the base so as to hide in the resting or in the inactive position, the energized contacts. These discs have as many openings as there are contacts so that simple rotation enables said contacts to be uncovered. They are locked or detained in the resting or in the inactive position and generally unlocked and rotated by manipulating the plug. Known locks or detents consist, for example, in the cooperation of a small piston or pin urged by a spring towards a locking position and of a conjugate housing formed in the disc so as to subject the latter to rotation with the base, said piston or pin being disengageable from its housing by an element of the plug.
The contacts of the plug and of the socket or base can be constituted respectively by pins and by recesses or bushes. However, the contacts of the base can also be constituted by resilient end-pressure contacts.
It is another object of the invention to provide a plug and socket electrical connector constituted by a fixed pin plug and a base having movable resilient end-pressure contacts and a safety disc of the type described above which is locked or indexed in position at least in part at the rest and at the contact positions, by the resilient action of the movable contacts of the base.